v3.3.1.900
Fair Value Disclosures - Fair Value of Financial Assets and Financial Liabilities (Detail) - USD ($)
$ in Millions
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2012
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]        
Cash and cash equivalents $ 6,083 $ 5,723 $ 4,390 $ 4,606
Long-term borrowings 4,930 4,922    
Carrying Amount [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]        
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]        
Cash and cash equivalents 6,083 5,723    
Accounts receivable 2,237 2,120    
Accounts payable and accrued liabilities 1,068 1,035    
Carrying Amount [Member] | Significant Other Observable Inputs (Level 2) [Member]        
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]        
Long-term borrowings 4,930 4,922    
Estimated Fair Value [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]        
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]        
Cash and cash equivalents 6,083 5,723    
Accounts receivable 2,237 2,120    
Accounts payable and accrued liabilities 1,068 1,035    
Estimated Fair Value [Member] | Significant Other Observable Inputs (Level 2) [Member]        
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]        
Long-term borrowings 5,223 5,309    
Consolidated Variable Interest Entities [Member]        
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]        
Cash and cash equivalents 148 278    
Long-term borrowings   3,389    
Consolidated Variable Interest Entities [Member] | Carrying Amount [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]        
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]        
Cash and cash equivalents 148 278    
Consolidated Variable Interest Entities [Member] | Estimated Fair Value [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]        
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]        
Cash and cash equivalents $ 148 $ 278